I. Field of the Invention
This invention relates to the automobile bi-direction remote control circuitry. There are wireless transmission circuitry and wireless receiving circuitry each on the remote control itself and the circuitry inside the automobile. The special feature of this invention is that the wireless transmission circuitry and wireless receiving circuitry apply the same specification of LO base band frequency circuitry. Based on this structure, it can reduce the number of components used in the bi-direction remote control, lower the circuitry cost and easy to manufacture.
II. Description of the Prior Art
Heretofore, current automobile remote controls have two types: the more popular single direction and the newer bi-direction inter-active controller. The current bi-direction remote control design as shown in FIG. 1 contains transmitting circuitries a,axe2x80x2, and receiving circuitries b,bxe2x80x2, both circuitry connect to push button c and the control circuitries d,dxe2x80x2. When the desired instruction is pressed from the push button c, the signal is generated from the transmission circuitry a and emitted from antenna exe2x80x2 to the circuitry inside the automobile. The circuitry inside the automobile receives the signal through antenna e and receiving circuitry bxe2x80x2. The signal is then sent into control circuitry dxe2x80x2 to execute the open door, lock door, start engine or initiate alarm system tasks. At the same time, the control circuitry dxe2x80x2 inside the automobile returns a signal back to the remote control through its control circuitry axe2x80x2 and antenna exe2x80x2. The remote control receives the feedback signal from antenna e and receiving circuitry b, finally to the control circuitry d, and converts the signal into images and display to confirm the success of the given instruction. These confirmations avoid error instructions and signal miss receiving conditions.
As shown on FIG. 2, current bi-direction remote control system has two wireless transmission circuitries a,axe2x80x2 and wireless receiving circuitries b,bxe2x80x2 on both remote control side and the circuitry inside the automobile. The two sets of circuitry are independent of each other. It functions as following: on the remote control side, the signals are transmitted from the wireless transmission circuitry a first and then passes through the LO base band frequency circuitry a1, amplified by the signal amplifier a2, finally those signals are emitted from the Antenna e. On the automobile side, these signals are received through the antenna exe2x80x2, then are amplified by the signal amplifier b1xe2x80x2, then go to the combination circuitry that is in parallel of the signal mixer b2xe2x80x2 and the LO base band frequency circuitry b3xe2x80x2; after the parallel circuitry, the signals now are converted into low frequency wave, then pass through the signal filter b4xe2x80x2 and the AM frequency sampler b5xe2x80x2, finally they reach the control circuitry dxe2x80x2 to finish the tasks. As described above, the control signals are initiated from the push button of the remote control; the feedback signals are triggered from the circuitry inside the automobile when it receives the control signals.
The major flaw of current remote control system design is: the wireless transmission circuitry and the wireless receiving circuitry are two independent circuitry; each of them equipped with an independent LO base band frequency circuitry to generate their base band frequency. This flaw not only increases the number of components but also might cause misplace for the different frequency circuitry, this further increases the cost and processes during manufacturing.
It is therefore a primary object of the invention to provide a new bi-direction remote control signal transmission circuitry design, wherein the remote control circuitry and the circuitry inside the automobile have the same specification. The wireless transmission circuitry and the wireless receiving circuitry apply the same LO base band circuitry, they are connected in the signal mixer of the wireless receiving circuitry and the signal amplifier of the wireless transmission circuitry. The invention can reduce the number of components and simplify the processes of manufacturing thus lower the total cost.